Advanced SAR imaging methods for forward-looking ground penetrating radar

Advanced SAR imaging methods for a dual-band fully polarimetric vehicle-based FLGPR are presented. The radar consists of two arrays (one at L-band and one at X-band) of wideband horns that form synthetic apertures as the vehicle advances. Model-based clutter suppression image processing is used to clean the SAR image obtained from the VV polarized L-band radar by employing a mixed binary mask. This surface clutter mask is formed from the second (X-band) frequency and the VH cross polarized L-band responses, neither of which appreciably scatter from buried objects. In addition, the volumetric wide band point spread function (PSF) which incorporates refraction at the nominal ground surface is determined. These approaches are tested with field-measured data, and subsurface targets are shown to be much easier to detect than by convention surface SAR imaging.